Dr. Khalid Askar is a UAE national faculty member in the Mechanical Engineering Department at Khalifa University. Dr. Askar began his studies at Purdue University, where he did research on molecular simulations of chemical reactions under both equilibrium and non-equilibrium conditions. He graduated shortly thereafter with a B.Sc. in Chemical Engineering and became a graduate student in the Chemical Engineering Department at the University of Florida with the prestigious MASDAR Fellowship. During his graduate studies, he worked on developing new colloidal self-assembly techniques, shape memory polymers and polymer composites with excellent antireflection and self-cleaning properties. He graduated with honors with his Masters and Ph.D. in Chemical Engineering from the University of Florida in August 2014.
Following that, he spent two years at MIT collaborating with Prof. Robert E. Cohen and Prof. Michael F. Rubner, who also served as his mentors, on research with focus on the development of a multifunctional polymer composite coating for desert based-solar cells. He is now one of the few UAE national faculty member in the Mechanical Engineering Department at Khalifa University. His group focuses on developing new coating methods to control orientation of specific nano-filler materials within different polymer matrices.
Dr. Askar's recent projects include the fabrication of a cost-efficient, multifunctional and durable coating that can easily be scaled up and applied onto different surfaces (buildings, car windshield, glass cover of solar panels, etc.). The optimized coating has many properties including: anti-reflection, 2) self-cleaning, abrasion resistance, self-healing, and anti-static.
His current research interests include developing corrosion resistant coatings protecting against degradation due to the harsh UAE desert climate conditions. The coating will utilize the high temperature and humidity in the UAE to trigger a self-healing mechanism to protect and shield the metal components against corrosion. Upon damage to the coating, the self-healing mechanism driven by the weather in the UAE will heal the surface.
Recent Research Projects
This research has demonstrated reversible recovery of optical transmittance and repairing of roughness, scratches, and other surface defects from nano to macro scale in ternary systems comprising epoxy/CAB semi-interpenetrating networks loaded with 1 vol% halloysite nanotubes. CAB mobility in the semi-interpenetrating networks upon heating, revealed by AFM, was the continual phenomenon in the self-healing mechanism.
A polyurethane (PU) foam with graphene embedded (and aligned) in the pore walls is pyrolyzed and then impregnated with PDMS to form a GF–PDMS nanocomposite, resulting in a slitlike network of graphene embedded in the viscoelastic PDMS matrix. The interconnected graphene network not only imparts excellent electrical conductivity (up to 2.85 S m–1, the conductivity of PDMS is 0.25 × 10–13 S m–1) to the composite but also enables ultrasensitive piezoresistive behavior.
A cheap and simple layer-by-layer method has been developed that can easily generate multilayer colloidal crystals that are uniform and highly ordered using electrostatic attraction combined with the Langmuir-Blodgett technique. These multilayer colloidal crystals mimic opals which are found in nature formed from years of sedimentation and compression of closely packed silica colloidal spheres resulting in a shiny iridescent color44-45. Another application to these colloidal crystals is in creating periodic dielectric three dimensional photonic crystals
Hollow tubular HNTs were used as reinforcement fillers in transparent epoxy composites. A spray coating process was used to control hydrodynamic flow to align the particles; at the same time the elevated levels of viscosity in HNTs suspensions preserved the HNT orientations upon impacting the substrate surface. By varying the viscosity and concentration it was demonstrated that the tube orientation could be controlled (horizontal, mixed, and vertical orientations).